Laundry treating machine and control method for the same

ABSTRACT

Embodiments of the present disclosure relate to a control method for a laundry treating machine comprising a first drum rotating step that is configured to rotate the drum at a preset reference RPM; a first water discharging step that is configured to rotate the impeller at a preset first water discharge RPM during the first drum rotating step; a second drum rotating step that is configured to rotate the drum at a first drum RPM lower than the reference RPM; a second water discharging step that is configured to rotate the impeller at a second water discharge RPM lower than the first water discharge RPM during the second drum rotating step, wherein a water level inside the first discharge pipe is kept on being higher than the highest water level inside the housing, while the first water discharging step and the second water discharging steps are performed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Korean Patent Application No.10-2019-0013825, filed on Feb. 1, 2019, and Korean Patent ApplicationNo. 10-2019-0046099, filed on Apr. 19, 2019, the entire contents ofwhich are hereby incorporated by reference in their entirety.

BACKGROUND OF THE DISCLOSURE Technical Field of the Disclosure

Embodiments of the present disclosure relate to a laundry treatingmachine and a control method for the same.

Background of the Disclosure

A laundry treating machine means an apparatus configured to washclothes. Among conventional laundry treating machines, a laundrytreating machine includes a cabinet; a tub that is mounted in thecabinet and configured to hold wash water; and a drum that is rotatablymounted in the tub and configured to hold clothes (hereinafter,laundry); a first discharge pipe configured to discharge the water heldin the tub to a water discharge pump; and a second discharge pipeconfigured to guide the water discharged from the water discharge pumpoutside the cabinet. The water discharge pump provided in such aconventional laundry treating machine is typically provided to flow thewater drawn into the first discharge pipe to the second discharge pipeby means of an impeller.

The conventional laundry treating machine having the above-notedstructure may be operated to perform a cycle of separating contaminantsfrom the laundry by rotating the drum after water is supplied to thetub; a cycle of discharging the water held in the tub; and a cycle ofremoving water or water elements from the laundry by rotating the drum(a spinning cycle).

The water discharge pump has to be actuated in the spinning cycle,because noise and vibration are likely to occur if the water held in thetub after separated from the laundry collides against the drum rotatingat a high rotation number.

However, the amount of the water separated from the laundry during thespinning cycle gets decreased as time passes. Thus, unless controllingthe rotation number of the impeller provided in the water dischargepump, noise and vibration might occur in the water discharge pumpdisadvantageously.

SUMMARY OF THE DISCLOSURE

Accordingly, an object of the present disclosure is to address theabove-noted and other problems.

Another object of the present disclosure is to provide a laundrytreating machine that may minimize noise and vibration of a waterdischarge pump configured to be actuated during a spinning cycle forremoving water from clothes, and a control method for the same.

Particular embodiments described herein include a method for controllinga laundry treating machine. The laundry treating machine may include acabinet; a tub mounted in a cabinet and configured to receive water; adrum rotatably mounted in the tub and configured to hold laundry; ahousing configured to receive water; an impeller rotatably supported inthe housing; and a discharge pipe configured to guide the water in thetub toward the housing. The method includes rotating the drum at apreset reference revolutions per minute (RPM); while rotating the drumat the reference RPM, rotating the impeller at a preset first waterdischarge RPM such that a level of water inside the discharge pipe ishigher than a highest water level inside the housing; rotating the drumat a first drum RPM lower than the reference RPM; and while rotating thedrum at the first drum RPM, rotating the impeller at a second waterdischarge RPM lower than the first water discharge RPM such that thelevel of water inside the discharge pipe remains higher than the highestwater level inside the housing.

In some implementations, the method can optionally include one or moreof the following features. The first water discharge RPM may be set tobe a predetermined RPM that maintains a first amount of the waterdischarged from the housing while rotating the impeller at the firstwater discharge RPM. The first amount of the water may be smaller than asecond amount of the water supplied to the discharge pipe while rotatingthe drum at the reference RPM. The second water discharge RPM may be setto be a predetermined RPM that maintains a third amount of the waterdischarged from the housing while rotating the impeller at the secondwater discharge RPM. The third amount of the water may be smaller than afourth amount of the water supplied to the discharge pipe while rotatingthe drum at the first drum RPM. The first water discharge RPM may beconfigured to be a variable RPM that increases based on a fifth amountof the water supplied to the housing increasing and decreases based onthe fifth amount of the water decreasing. The method may includecontrolling a vibration sensor to measure vibration of the drum whilerotating the drum at the first drum RPM; rotating the drum at a seconddrum RPM; and rotating the impeller at a third water discharging RPMwhile rotating the drum at the second drum RPM. The third waterdischarge RPM may be configured to maintain a sixth amount of the watersupplied to the housing while rotating the drum at the second drum RPM,the sixth amount of the water being larger than a seventh amount of thewater discharged from the housing while rotating the impeller at thethird water discharge RPM. The third water discharge RPM may beconfigured to be a variable RPM that increases based on an eighth amountof the water supplied to the housing increasing and decreases based onthe eighth amount of the water decreasing. The method may includepausing the rotation of the drum based on the measured vibration beinggreater than a reference value; and pausing the rotation of the impellerbased on the measured vibration being greater than the reference value.The method may include, based on completion of pausing the rotation ofthe drum and pausing the rotation of the impeller, alternately repeatingclockwise and counter-clockwise rotations of the drum; and based oncompletion of alternately repeating the clockwise and counter-clockwiserotations of the drum, performing: rotating the drum at the referenceRPM; while rotating the drum at the reference RPM, rotating the impellerat the first water discharge RPM; rotating the drum at the first drumRPM; and while rotating the drum at the first drum RPM, rotating theimpeller at the second water discharge RPM. The method may include,based on completion of pausing the rotation of the drum and pausing therotation of the impeller, alternately repeating clockwise andcounter-clockwise rotations of the drum; and based on completion ofalternately repeating the clockwise and counter-clockwise rotations ofthe drum, performing: rotating the drum at the first drum RPM; and whilerotating the drum at the first drum RPM, rotating the impeller at thesecond water discharge RPM. The laundry treating machine may include animpeller driver configured to rotate the impeller. The discharge pipemay be a first discharge pipe. The laundry treating machine may includea second discharge pipe configured to guide the water discharged fromthe housing out of the cabinet. The laundry treating machine may includea water discharge pump, wherein the water discharge pump includes thehousing and the impeller.

Embodiments of the present disclosure may provide a control method for alaundry treating machine comprising a tub that is mounted in a cabinetand holds water; a drum that is rotatably mounted in the tub and holdslaundry; a drum drive part that is configured to rotate the drum; ahousing that defines a predetermined space for storing water; animpeller that is rotatably provided in the housing; an impeller drivepart that is configured to rotate the impeller; a first discharge pipethat is configured to guide the water held in the tub to the housing anda second discharge pipe that is configured to guide the water dischargedfrom the housing to the outside of the cabinet, the control methodcomprising: a first drum rotating step that is configured to rotate thedrum at a preset reference RPM; a first water discharging step that isconfigured to rotate the impeller at a preset first water discharge RPMduring the first drum rotating step; a second drum rotating step that isconfigured to rotate the drum at a first drum RPM lower than thereference RPM; a second water discharging step that is configured torotate the impeller at a second water discharge RPM lower than the firstwater discharge RPM during the second drum rotating step, wherein awater level inside the first discharge pipe may be kept on being higherthan the highest water level inside the housing, while the first waterdischarging step and the second water discharging steps are performed.

The first water discharge RPM may be set to be a predetermined RPM thatkeeps the amount of the water discharged from the housing during thefirst water discharging step on being smaller than the amount of thewater supplied to the first discharge pipe during the first drumrotating step.

The water discharge RPM may be set to be a predetermined RPM that keepsthe amount of the water discharged from the housing during the secondwater discharging step on being smaller than the amount of the watersupplied to the first discharge pipe during the second drum rotatingstep.

The first water discharge RPM may be set to be a variable RPM thatincreases when the amount of the water supplied to the housing increasesand decreases when the amount of the water decreases.

The control method for the laundry treating machine may furthercomprising a vibration measuring step that is configured to control avibration sensing part to measure vibration of the drum during thesecond drum rotating step; and a third water discharging step that isconfigured to rotate the impeller at a third water discharging RPMduring the third drum rotating step.

The third water discharge RPM may be set to be a predetermined RPM thatkeeps the amount of the water supplied to the housing during the thirddrum rotating step on being bigger than the amount of the waterdischarged from the housing during the third water discharging step.

The third water discharge RPM may be set to be a variable RPM thatincreases when the amount of the water supplied to the housing increasesand decreases when the amount of the water decreases.

The control method for the laundry treating machine may further comprisea drum braking step that is configured to pause the rotation of the drumand an impeller braking step that is configured to pause the rotation ofthe impeller, that are performed when the measured vibration is biggerthan the reference value.

The control method for the laundry treating machine may further comprisean agitating step that is configured to alternately repeating aclockwise direction drum rotation and a counter-clockwise direction drumrotation, after the drum braking step and the impeller braking step arecompleted, wherein the first drum rotating step, the first waterdischarging step, the second drum rotating step and the second waterdischarging step may be re-performed after the agitating step iscompleted.

The control method for the laundry treating machine may further comprisean agitating step that is configured to alternately repeating aclockwise direction drum rotation and a counter-clockwise direction drumrotation, after the drum braking step and the impeller braking step arecompleted, wherein the second drum rotating step and the second waterdischarging step may be re-performed after the agitating step iscompleted.

The present disclosure has the effect of providing a laundry treatingmachine that may minimize noise and vibration of a water discharge pumpconfigured to be actuated during a spinning cycle for removing waterfrom clothes, and a control method for the same.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description given herein below and the accompanying drawings,which are given by illustration only, and thus are not limitative of thepresent disclosure, and wherein:

FIGS. 1 to 2B are diagrams illustrating one embodiment of a laundrytreating machine; and

FIG. 3 is a diagram illustrating one embodiment of a control method forthe laundry treating machine.

DESCRIPTION OF SPECIFIC EMBODIMENTS

Hereinafter, referring to the accompanying drawings, exemplaryembodiments of the present disclosure will be described. Regardless ofnumeral references, the same or equivalent components may be providedwith the same reference numbers and description thereof will not berepeated.

A laundry treating machine 100 according to one embodiment may include acabinet 1; a tub 2 that is provided in the cabinet and configured tohold water; and a drum 3 that is rotatably mounted in the tub 2 andholds laundry (e.g., clothes); a water supply part 561 and 563configured to supply water to the tub; and a water discharge part 6configured to discharge the water held in the tub outside the cabinet.

The cabinet 1 may have a cabinet opening 11 that is provided tofacilitate communication between the inside and outside of the cabinet.The cabinet opening 11 may be open and closed by a door 13 that isrotatably coupled to the cabinet 1.

The tub 2 may include a cylinder-shaped tub body 21 having an innerempty space and a tub opening 23 that is provided in a front surface ofthe tub body. The tub opening 23 may be connected with the cabinetopening 13 through an insulation portion. The insulation portion forconnecting the cabinet opening 11 and the tub opening 23 with each othermay be configured to block the water held in the tub body 21 from beingdischarged to the cabinet 1 through the tub opening 23 and also dampenthe vibration of the tub body 21 from being transferred to the cabinet1.

The insulation portion may have an insulating body 41 that is formed ofa flexible material (e.g., rubber) to connect the cabinet opening 11 andthe tub opening 23 with each other. The insulating body 41 may be formedof a cylinder-shaped flexible body with one body fixed to the cabinetopening 11 and the other end fixed to the tub opening 23.

The tub body 21 may be mounted in the cabinet 1 by means of a tubsupport part. The tub support part may include a spring 25 provided toan upper area of a circumferential surface of the tub body 21 to thecabinet 1; and a damper 26 provided to fix a lower area of thecircumferential surface to the cabinet.

A heater 273 configured to heat the water held in the tub may beprovided in the tub body 21. The heater may be provided in a heatingchamber 271 that is formed in the lower area of the circumferentialsurface of the tub body 21 (which is the area located lower than arotation center of the drum). The heating chamber 271 may be provided asa predetermined space that projects from a bottom of the tub bodytowards a bottom of the cabinet, so as to collect the water stored inthe tub body 21.

The drum 3 may include a drum body 31 that is rotatable in the tub body21. The drum body 31 may be formed of a cylinder-shaped body having aninner empty space. Drum-through holes 32 may be formed incircumferential, front and rear surfaces of the drum body 31,respectively, to facilitate communication between the drum body insideand the tub body inside. A drum opening 33 may be formed in a surfacethat is directed towards the cabinet opening 11 (e.g., a front surfaceof the drum) in the space defined by the drum body 31.

The drum body 31 may be rotatable by a drum drive part 35. The drumdrive part may include a stator 351 that is fixed to a rear surface ofthe tub body 21 and configured to generate a rotating field; a rotor 353that is provided outside the tub body 21 and configured to be rotated bythe rotating field; and a shaft 355 that penetrates a rear surface ofthe tub body 21 and connects the rotor 353 with the drum body 31.

The laundry treating machine 100 may further include a detergent supplypart 5 that is configured to supply a washing detergent to the tub body21. The detergent supply part 5 may include a case 51 that is providedin the cabinet 1; and a drawer 52 that is withdrawable from the case 41.

The drawer 52 mounted in the case 51 may be withdrawn out of the cabinet1 through a drawer introduction hole that is formed through a frontsurface of the cabinet. The drawer 52 may be formed in a polyhedronshape (e.g., a hexahedron) with an open top. The drawer may include astorage 521 that defines a predetermined space for storing a washingdetergent; and a detergent outlet hole 523 that is in communication withthe storage 521 and the case 51. The detergent outlet hole 523 may be athrough-hole that penetrates a rear surface or a bottom surface of thestorage 521 or it may be a bell trap that is provided in the bottom ofthe storage 521.

In this instance, the water supply part may include a water supply pipe561 configured to supply water to the storage 521 from an external watersupply; and a water supply valve 563 configured to open or close thewater supply pipe 561 based on a control signal of a controller (notshown). Accordingly, when water is supplied to the storage 521 thatstores the washing detergent therein through the water supply pipe 561,the washing detergent may flow to the case 51 through the detergentoutlet hole 523, together with the washing detergent stored in thestorage 521.

The water and washing detergent that are discharged to the case 51 maybe supplied to the tub body 21 through the insulating body 41. For that,an inlet pipe 43 may be provide in the insulating body 41 to lead in thewater and washing detergent and a supply pipe 53 may be provided in thedetergent supply part 5 to guide the detergent and water towards theinlet pipe 43. The inlet pipe 42 and the supply pipe 53 may be formed ofa flexible material (e.g., rubber). That is to minimize the vibration ofthe tub that is transferred to the case 51 and the front panel 15 viathe inlet pipe 42 and the supply pipe 53.

The water held in the tub body 21 may be discharged outside the cabinet1 through the water discharge part 6.

The water discharge part 6 may include a chamber 61 that defines apredetermined space for storing water; a first discharge pipe 63 that isconfigured to guide the water from the tub body 21 to the chamber 61;and a water discharge pump 65 configured to flow the water held in thechamber 61 towards a second discharge pipe 67. The second waterdischarge pipe 67 may be provided as means for guiding the waterdischarged from the water discharge pump 65 towards the outside of thecabinet 1. The highest point of the second discharge pipe 67 may pass apreset point that is higher than the lowest point of the tub opening 23.The first discharge pipe 63 may connect the heating chamber 271 and thechamber 61 with each other.

The chamber 61 may include a filter 613 configured to filter the waterdischarged from the tub. The chamber 61 may be provided in a cylindershape having a communication hole 611 that is formed in a front surfacethereof. The communication hole 611 may be in communication with afilter coupling hole (not shown) that is formed through the frontsurface of the cabinet. In this instance, a user is able to insert thefilter 613 through the filter coupling hole.

The water discharge pump 65 may include a first housing 651 provided tocommunicate with the chamber 61 and define a predetermined space forstoring water; a first impeller 655 that is rotatable in the firsthousing; a first impeller motor 657 configured to rotate the firstimpeller; and an outlet hole 653 penetrating a circumferential surfaceof the first housing and connected with the second water discharge pipe67.

The laundry treating machine 100 may further include vibration sensingpart 7 that is configured to measure presence of vibration in the tubbody 21 and the size of the vibration generated in the tub body. Thedrum body 31 may be connected to the rotor 353 by means of the shaft 355penetrating the rear surface of the tub body 21. Accordingly, thelaundry treating machine 100 may sense the vibration in the drum body 31by means of the vibration sensing part 7.

In addition, the laundry treating machine 100 may further include awater level sensing part 8 that is configured to sense a water levelinside the tub body 21. The water level sensing part 8 may include acommunication pipe 81 having water level scales that are equal to thewater level scales inside the tub body 31; and a sensor 83 configured tosense pressure variation inside the communication pipe 81.

The communication pipe 81 may have one end connected to the firstdischarge pipe 382 and the other end located higher than the rotationcenter (e.g., along an axis of the shaft 355) of the drum body 31.Accordingly, once all of the water flows into the first discharge pipe63 from the tub body, the water level sensing part 8 may also sense awater level of the first discharge pipe 63.

When actuating the water discharge pump 65 during a spinning cycle forremoving water or water element from the laundry, noise and vibrationare likely to occur in the laundry treating machine 100 having theabove-noted structure. A large amount of water is supplied to the waterdischarge pump 65 in an early stage of the spinning cycle. As thespinning cycle progresses, the amount of the water supplied to the waterdischarge pump 65 may decrease such that the water level inside thehousing 651 may become lower than an upper end of the impeller 655. Whenthe impeller 655 is rotated in a state where the water level inside thehousing 651 is lower than the upper end of the impeller 655, thefriction between the impeller 655 and the water might cause noise andvibration.

FIGS. 2A and 2B illustrate a state where the water level inside thehousing 651 becomes lower than the upper end of the impeller 655, whenthe spinning cycle and the water discharge process are performedsimultaneously. FIG. 2A illustrates a state where a much amount oflaundry is loaded into the drum body 31 enough to lower the tub body 21towards the bottom of the cabinet. FIG. 2B illustrates a state where thelowering of the tub body 21 does not happen.

When the tub body 21 is not lowered (see FIG. 2A), even one end of thefirst discharge pipe 63 connected to the heating chamber 271 may belowered towards the bottom of the cabinet 1 and a water trap would beformed in the first discharge pipe 63. If such a water trap is formed inthe first discharge pipe 63, noise and vibration might be caused by thewater discharge pump more often.

FIG. 3 illustrates a control method for the laundry treating machinewhich may minimize the noise and vibration caused by the water dischargepump, when the spinning and the water discharging are performedsimultaneously.

The control method shown in FIG. 3 may be applied to a spinning processand a water discharging that are performed in a washing cycle, or awater discharging process that is performed in a spinning cycle. Thewashing cycle may be configured to rotate the drum and separate foreignsubstances or contaminants from the laundry after water and a washingdetergent are supplied to the tub. The rinsing cycle may be configuredto rotate the drum after supplying water to the tub and separate theforeign substances from the laundry. The spinning cycle may beconfigured to rotate the drum and separate water from the laundry.

The control method for the laundry treating machine may include a firstdrum rotating step S10 configured to rotate the drum 3 at a presetreference RPM (Revolution Per Minute) and remove water from the laundry;a first water discharging step S20 configured to rotate the impeller 655at a preset first water discharge RPM during the first drum rotatingstep S10; a second drum rotating step S30 configured to rotate the drum3 at a first drum RPM that is lower than the reference RPM; and a secondwater discharging step S40 configured to rotate the impeller 655 at asecond water discharge RPM that is lower than the first water dischargeRPM.

The control method for the laundry treating machine is characterized inthat water levels inside the first discharge pipe 63 is kept beinghigher than the highest water level inside the housing 651 during thefirst and second water discharging steps S20 and S40.

In other words, the first water discharge RPM may be set to be apredetermined RPM that may keep the amount of the water discharged tothe second discharge pipe 67 from the housing 651 during the first waterdischarging step S20 to be smaller than the amount of the water suppliedto the first discharge pipe 63 during the first drum rotating step S10.

Similarly, the second water discharge RPM may be set to be apredetermined RPM that may keep the amount of the water discharged tothe second discharge pipe 67 from the housing 651 during the secondwater discharging step S40 to be smaller than the amount of the watersupplied to the first discharge pipe 63 during the second drum rotatingstep S30.

When the first and second water discharge RPMs are controlled asmentioned above, the water level inside the housing 651 may be preventedfrom getting lower than the upper end of the impeller 655. Accordingly,the control method may minimize the noise and vibration caused in thewater discharge pump during the spinning by means of the above-notedsteps.

Meanwhile, the first water discharge RPM and the second water dischargeRPM may not be fixed RPMs but set to be variable (as a variable RPM)based on the amount of the water supplied to the housing 651. In otherwords, the first and second water discharge RPMs may be set to bevariable based on the water levels inside the first discharge pipe 63that are measured by the water level sensing part 8.

In this instance, the first and second water discharge RPMs may becontrolled to increase, when the amount of the water supplied to thehousing 651 increases, and decrease, when the amount of the waterdecreases. Here, the RPM increase has to be controlled to keep the waterlevel in the first discharge pipe 63 on being higher than the highestwater level inside the housing 651.

During the second drum rotating step S30, the control method for thelaundry treating machine may implement a vibration measuring step S50configured to control the vibration sensing part 7 to measure vibrationin the drum body 31; and a vibration determining step S51 configured todetermine whether the vibration measured in the vibration measuring stepS50 is a preset reference value or less.

When the measured vibration is the preset reference value or less, thecontrol method may implement a first drum rotating step S70 configuredto rotate the drum body 31 at a second drum RPM that is higher than thereference RPM and separate water from the laundry. The reason why thevibration measuring step S50 is performed before the third drum rotatingstep S70 is to prevent a big vibration from occurring when rotating thedrum body 31 at a high RPM.

When rotating the drum body 31 in a state where the laundry is in closecontact with some area of the drum body 31, the rotation center of thedrum body 31 may be eccentric not to be equal to the rotation center ofthe drum drive part. The drum body 31 rotating in the eccentric state islikely to cause vibration and the vibration may become bigger as theeccentricity becomes bigger (it means that it may become bigger as thedistance between the shaft and the rotation center of the drum bodybecomes farther). Accordingly, the control method may implement thefirst drum rotating step S70 only when the vibration of the tub body 31is the reference value or less and then minimize the vibration of thetub body 21 that might be generated during the third drum rotating stepS70.

During the third drum rotating step S70, the control method mayimplement a third water discharging step S60 that is configured torotate the impeller 655 at a third water discharge RPM. In the thirdwater discharging step S60, a water level inside the first dischargepipe 63 has to be kept being higher than the highest level inside thehousing 651 so as to minimize the noise and vibration caused by thewater discharge pump. Accordingly, the first water discharging RPM hasto be set to be a predetermined RPM that may keep the amount of thewater supplied to the housing 651 from the first discharge pipe 63during the third drum rotating step S70 on being higher than the amountof the water discharged to the second discharge pipe 67 from the housing651.

In addition, the third water discharge RPM may be set to be a variableRPM that may increase, when the amount of the water supplied to thehousing 651 increases, and decrease, when the amount decreases.

The third drum rotating step S70 may be performed for a predeterminedtime period that is set in the third drum rotating step. Once the timeperiod passes, the control method may perform a drum braking step S90configured to end the rotation of the drum body; and an impeller brakingstep S80 configured to end the rotation of the impeller.

Meanwhile, when the vibration measured in the vibration measuring stepS50 is larger than the reference value, the control method perform aneccentricity relieving step that is configured to reduce the vibrationof the drum body 31.

The eccentricity relieving step may include a drum braking step S53configured to pause the rotation of the drum body 31; an impellerbraking step S55 configured to pause the rotation of the impeller 655;and an agitating step S57 configured to alternately agitating clockwiseand counter-clockwise direction rotations of the drum body 31. Theagitating step S57 may start once the drum braking step S53 and theimpeller braking step S55 are completed.

After the completion of the agitating step S57, the control method mayre-start the first drum rotating step S10, the first water dischargingstep S20, the second drum rotating step S30 and the second waterdischarging step S40.

To reduce the time taken by the spinning, the control method mayre-perform the second drum rotating step S30 and the second waterdischarging step S40 after completing the agitating step S57.

The control method applied to a front loading type laundry treatingmachine is described above, which includes the cabinet opening 11provided in the front surface of the cabinet. However, the controlmethod may be applied even to a top loading type laundry treatingmachine which includes the cabinet opening provided in the top surfaceof the cabinet. The tub opening is provided in the top surface of thetub body and the drum opening is provided in the top surface of the drumbody. The shaft of the drum body is provided through the bottom surfaceof the tub body. That type having the above structure is one example ofthe top loading type laundry treating machine.

As the present features may be embodied in several forms withoutdeparting from the characteristics thereof, it should also be understoodthat the above-described embodiments are not limited by any of thedetails of the foregoing description, unless otherwise specified, butrather should be considered broadly within its scope as defined in theappended claims, and therefore all changes and modifications that fallwithin the metes and bounds of the claims, or equivalents of such metesand bounds, are therefore intended to be embraced by the appendedclaims.

What is claimed is:
 1. A method for controlling a laundry treatingmachine, wherein the laundry treating machine comprises: a cabinet; atub mounted in a cabinet and configured to receive water; a drumrotatably mounted in the tub and configured to hold laundry; a housingconfigured to receive water; an impeller rotatably supported in thehousing; and a discharge pipe configured to guide the water in the tubtoward the housing, the method comprising: rotating the drum at a presetreference revolutions per minute (RPM); while rotating the drum at thereference RPM, rotating the impeller at a preset first water dischargeRPM such that a level of water inside the discharge pipe is higher thana highest water level inside the housing; rotating the drum at a firstdrum RPM lower than the reference RPM; and while rotating the drum atthe first drum RPM, rotating the impeller at a second water dischargeRPM lower than the first water discharge RPM such that the level ofwater inside the discharge pipe remains higher than the highest waterlevel inside the housing.
 2. The method of claim 1, wherein the firstwater discharge RPM is set to be a predetermined RPM that maintains afirst amount of the water discharged from the housing while rotating theimpeller at the first water discharge RPM, the first amount of the waterbeing smaller than a second amount of the water supplied to thedischarge pipe while rotating the drum at the reference RPM.
 3. Themethod of claim 2, wherein the second water discharge RPM is set to be apredetermined RPM that maintains a third amount of the water dischargedfrom the housing while rotating the impeller at the second waterdischarge RPM, the third amount of the water being smaller than a fourthamount of the water supplied to the discharge pipe while rotating thedrum at the first drum RPM.
 4. The method of claim 2, wherein the firstwater discharge RPM is configured to be a variable RPM that increasesbased on a fifth amount of the water supplied to the housing increasingand decreases based on the fifth amount of the water decreasing.
 5. Themethod of claim 1, further comprising: controlling a vibration sensor tomeasure vibration of the drum while rotating the drum at the first drumRPM; rotating the drum at a second drum RPM; and rotating the impellerat a third water discharging RPM while rotating the drum at the seconddrum RPM.
 6. The method of claim 5, wherein the third water dischargeRPM is configured to maintain a sixth amount of the water supplied tothe housing while rotating the drum at the second drum RPM, the sixthamount of the water being larger than a seventh amount of the waterdischarged from the housing while rotating the impeller at the thirdwater discharge RPM.
 7. The method of claim 5, wherein the third waterdischarge RPM is configured to be a variable RPM that increases based onan eighth amount of the water supplied to the housing increasing anddecreases based on the eighth amount of the water decreasing.
 8. Themethod of claim 5, further comprising: pausing the rotation of the drumbased on the measured vibration being greater than a reference value;and pausing the rotation of the impeller based on the measured vibrationbeing greater than the reference value.
 9. The method of claim 8,further comprising: based on completion of pausing the rotation of thedrum and pausing the rotation of the impeller, alternately repeatingclockwise and counter-clockwise rotations of the drum; and based oncompletion of alternately repeating the clockwise and counter-clockwiserotations of the drum, performing: rotating the drum at the referenceRPM; while rotating the drum at the reference RPM, rotating the impellerat the first water discharge RPM; rotating the drum at the first drumRPM; and while rotating the drum at the first drum RPM, rotating theimpeller at the second water discharge RPM.
 10. The method of claim 8,further comprising: based on completion of pausing the rotation of thedrum and pausing the rotation of the impeller, alternately repeatingclockwise and counter-clockwise rotations of the drum; and based oncompletion of alternately repeating the clockwise and counter-clockwiserotations of the drum, performing: rotating the drum at the first drumRPM; and while rotating the drum at the first drum RPM, rotating theimpeller at the second water discharge RPM.
 11. The method of claim 1,wherein the laundry treating machine includes an impeller driverconfigured to rotate the impeller.
 12. The method of claim 1, whereinthe discharge pipe is a first discharge pipe, and wherein the laundrytreating machine includes a second discharge pipe configured to guidethe water discharged from the housing out of the cabinet.
 13. The methodof claim 1, wherein the laundry treating machine includes a waterdischarge pump, wherein the water discharge pump includes the housingand the impeller.